The oldest water pump, perhaps, can be considered a mill wheel with attached to it jugs. Such a device is capable of raising water to a small height, usually not exceeding several meters. Despite the apparent simplicity of the design, such water pumps in the Middle Ages of the last millennium in the Netherlands were drained huge crop areas. The engine of the mechanisms was the blades of windmills.
At present, a lot of various technical solutions are used for pumping liquids. Water is pounded under the pistons, pushed with screws and augers, twirled between gear teeth, sucked into sparse zones created by jets of gas or the same liquid, and so on.
But there is one design, invented, incidentally, not so long ago - in the 18th century, which is now used at times more often than its "colleagues."
The device of the centrifugal water pump
A distinctive feature of this construction is simplicity. The centrifugal water pump consists of only two parts - the cochlea (the body of the device) and the wheel. When the latter is set in motion, its blades carry along the liquid in the pump, causing it to rotate.
As a result, centrifugal force begins to act on the water. It "presses" the liquid against the outer walls of the body. In technical terms, this means that a zone of increased pressure is created around the outer circumference, which pushes water into the pressure channel. In the center of the wheel, on the contrary, a rarefaction zone is formed, due to which liquid from the suction nozzle enters the center of the cochlea.
The blades of the pressure wheel are given a curved shape, due to this solution, the blades are, as it were, pushed out the liquid outwards. The pressure created by a centrifugal pump with curved blades is higher.
Classification of pumps
Devices that allow pumping liquids have different designs. But all of them are conditionally divided into two large groups - discrete and continuous action.
The water centrifugal pump belongs to a group of continuous devices. In addition to this group, there are also axial structures. What it is? The axial pump is a pipe inside which is installed a screw (in the form of blades or auger). When rotating, the fluid begins to move along the pipe along the axis, from where the pump name is also axial. This design is very efficient, but can not boast of considerable pressure. Pumps of continuous action are also jet and vortex (ring).
The most striking example of a discrete (volumetric) pump is a piston pump. The second option, often used in engineering, is a gear design. Volumetric pumps differ from continuous by much higher pressure, but their performance is less.
Features and benefits of centrifugal pumps
The centrifugal water pump is deservedly popular with designers for several reasons. One of these is, of course, the phenomenal simplicity of the design. They are more often than others found in boiler houses and water supply units. The repair of water centrifugal pumps is most often reduced to replacing the shafts of the drive shaft and bearings. From long-term work from time to time wears out, undergoing corrosion, the impeller (impeller). More in the pump just nothing to break, which can not be said about any other design, for example piston.
The centrifugal water pump is not capable of creating the pressure available to the reciprocating pump. But such designs can be made multistage, when each subsequent stage increases the value of pressure. Such a solution allows to obtain an output of up to 100 kgf / cm 2 at the output.
Due to the simplicity of construction and excellent performance characteristics, centrifugal pumps have no equal in heat power and water supply. They are also responsible for safety. So, water pumps of the vast majority of modern fire trucks are centrifugal.
A lot of miniature designs of centrifugal pumps are found in engineering. So, for example, the pump of a windscreen washer of a car, fuel pumps of an injector engine are, as a rule, products made on a centrifugal scheme.
A centrifugal water pump with its own hands sometimes makes use of homegrown Kulibins for watering beds in the private sector. Their crafts are various rotating structures of pipes. The water located in such pipes under the influence of the same centrifugal force flies out of the channel, and due to rapid rotation it is well dispersed.